Let's learn about hypoxemia - a decrease in oxygen in the blood!

Do you sometimes feel like you're short of breath? Or like your chest is a little tight? One reason for this could be a decrease in the oxygen level in your blood. This is what we medically call hypoxemia. Although this can be a serious condition, it can be managed well if you understand it properly and do the necessary things. So, let's talk about this in a little more detail today, shall we?

What is Hypoxemia?

Simply put, hypoxemia is when our blood has less oxygen than it should. Think of it this way: our bodies are like a car. Just as a car needs gasoline to run, every organ and cell in our body needs oxygen to function properly.

This oxygen enters our blood through the lungs when we breathe. When we breathe, the oxygen in the air goes into our lungs. Inside the lungs are tiny air sacs, like tiny grapes on a vine. We call these `(Alveoli)` . Around these `(Alveoli)` are spread many fine blood channels `(Capillaries) . When we breathe, the oxygen in the air that comes in is absorbed into these `(Alveoli)` through those fine blood channels. Then this oxygen travels with the blood throughout the body and reaches our tissues.

So, if there is a problem somewhere in this process, that is, if there is not enough oxygen in the breath we take, or if the lungs are not able to absorb oxygen into the blood properly, then the oxygen level in the blood decreases, which means hypoxemia occurs.

Hypoxemia can have a variety of effects, depending on its severity and duration . Sometimes it can cause mild symptoms like headaches and shortness of breath. But in severe cases, it can interfere with the functioning of the heart and brain, cause a condition called ``Hypoxia``, where the body's organs and tissues are deprived of oxygen, and can even lead to death.

When this occurs in the short term, we call it "acute respiratory failure," and when it is a problem that continues for months or years, we call it "chronic respiratory failure."

What is the difference between Hypoxemia and Hypoxia?

You may have heard the terms hypoxemia and hypoxia. While they sound the same, there is a slight difference.

• Hypoxemia is a decrease in oxygen in the blood.
• Hypoxia is a decrease in the amount of oxygen reaching our body's tissues.

Hypoxia is often caused by a condition called hypoxemia. This means that when the blood has low oxygen levels, the tissues also have low oxygen levels. But that's not always the case. Sometimes, the tissues can be low in oxygen even though the blood has normal oxygen levels, or the tissues can be low in oxygen even though the blood has low oxygen levels. It's a bit complicated, but the key is that both are related to low oxygen levels.

Who is more likely to develop hypoxemia?

Although anyone can develop this condition called hypoxemia, some people are at higher risk of developing it.

• This risk is especially high for people with lung diseases, for example, asthma, COPD (Chronic Obstructive Pulmonary Disease), and pneumonia.
• This can also affect people with heart disease . Because the heart is the one that pumps oxygen-rich blood throughout the body. So if there is any problem with the functioning of the heart, it will also affect the oxygen levels in the blood.
• In addition, some infectious diseases such as influenza, pneumonia, and COVID-19 can also increase the risk of hypoxemia.

What are the symptoms of this?

Okay, now let's see what are the symptoms we see in this condition of hypoxemia. These symptoms can vary depending on the severity of the disease, that is, how low the oxygen is, and what is the cause.

• Headache: Frequent headaches.
• Dyspnea: A feeling of difficulty breathing, tightness in the chest, and shortness of breath.
• Tachycardia: An increase in the rate of the heart beat.
• Cough: A persistent cough.
• Wheezing: A whistling sound coming from the chest when breathing.
• Confusion: Feeling dizzy and not knowing what to do.
• Blue skin, nails, and lips (Cyanosis): This is a more serious symptom. When the body doesn't get enough oxygen, sometimes the skin, nails, and lips can turn blue.

What are the main causes of hypoxemia?

Hypoxemia can have many causes. But most often, the main cause is an underlying medical condition. This means that a heart or lung disease that affects breathing or blood circulation is often the cause. Some medications can also cause hypoxemia by slowing breathing.

You may have heard of a condition called `(Sleep Apnea)`. It is a condition in which breathing stops intermittently during sleep. In such conditions, or in people with mild lung diseases, the oxygen level in the blood can decrease at night. This is called `(Nocturnal Hypoxemia)`.

Another thing is that hypoxemia can also occur when traveling to high altitudes . Imagine that when you go to a high mountainous area like Nuwara Eliya, that's why some people feel like they have difficulty breathing. This is because the amount of oxygen in the air decreases as the altitude increases.

A few more reasons...

Some other conditions that can cause hypoxemia include:

• Acute Respiratory Distress Syndrome (ARDS)
• Anemia - that means lack of blood
• Asthma
• Bronchitis
• Chronic Obstructive Pulmonary Disease (COPD)
• Congenital heart defects - heart diseases that are present at birth
• Congestive heart failure
• Emphysema - damage to the air sacs in the lungs
• Pneumonia
• Air around the lungs or lung collapse (Pneumothorax)
• Pulmonary edema
• Pulmonary embolism
• Scarring of the lungs (Pulmonary fibrosis)
• Pulmonary hypertension

5 main categories of factors that contribute to hypoxemia

Now let's look at the 5 main mechanisms that contribute to the occurrence of hypoxemia. These are a bit medical, but let's try to understand them simply.

1. Ventilation-Perfusion (V/Q) mismatch: Think about it, for the blood to receive oxygen, the lungs need to get enough air (this is called ventilation), and to carry that oxygen, the lungs need to get enough blood (this is called perfusion). If there is a problem with either of these two, for example, if the lungs get enough air but not enough blood, or if the blood gets enough air but not enough air, then oxygen does not get into the blood properly. This is called a `(V/Q) mismatch`. This is often due to heart disease or lung disease.

2. Diffusion impairment: Sometimes the lungs get enough air and blood, but it becomes difficult for the oxygen in the lungs to be absorbed (diffused) into the blood vessels. Just like when the pores of a filter become clogged, water cannot pass through. This can happen due to conditions like emphysema or scarring of the lungs.

3. Hypoventilation: This is when we breathe too deeply or too slowly. This means that not enough oxygen is getting to the lungs. This can be caused by many lung diseases and some brain diseases.

4. Low environmental oxygen: If the air in our environment is low in oxygen, no matter how much we breathe, our body will not get the oxygen it needs. As I mentioned before, the air in high mountain areas is low in oxygen.

5. Right-to-left shunting: Normally, the oxygen-poor (poor) blood in our body goes to the right side of the heart, from there it goes to the lungs to pick up oxygen (purify), and then goes back to the left side of the heart and is pumped throughout the body. However, in some people, this oxygen-poor blood can go directly from the right side of the heart to the left side of the body instead of going to the lungs. Then, the oxygen-poor blood goes throughout the body. This is called right-to-left shunting. Most of the time, this happens because of some abnormality in the heart.

How do you diagnose this?

Okay, now let's see how a doctor diagnoses this condition of hypoxemia. When you go to see a doctor, he will first listen to your heart and lungs. Because any abnormalities in these organs can be a sign of low oxygen in the blood. He will also check if your skin, lips, and fingernails are blue.

In addition, you can do the following tests to check your oxygen levels:

• Pulse oximetry: You've probably seen this. It's a small device that clips onto your finger and measures the oxygen level in your blood. It's painless and doesn't require blood. Many doctors use it during routine checkups.
• Arterial blood gas test: This is a test that accurately measures the oxygen level in the blood by taking a small blood sample from a place such as the wrist, the crook of the arm, or the groin.
• Six-minute walk test (6MWT): This involves walking on a flat surface for six minutes, measuring how your oxygen levels change and how far you can walk. This can give you an idea of ​​how well your lungs and heart are working.

What are the treatments?

When treating hypoxemia, the treatment depends on the cause. Your doctor may give you supplemental oxygen to increase the oxygen levels in your blood. This can be given through oxygen tanks or machines called oxygen concentrators. Some people may need it continuously, while others may only need it when they are tired. It depends on the severity of the condition.

In severe hypoxemia conditions, such as acute respiratory distress syndrome (ARDS), a machine called a ventilator may be used to help you breathe.

The key is to treat the underlying cause. For example:

• People with lung diseases like COPD may be given inhalers , which contain either bronchodilators or steroids.
• Diuretics can be given to remove excess fluid from the lungs.
• You may be asked to use a CPAP (Continuous Positive Airways Pressure) mask to treat sleep apnea.
• If there is a risk of continued hypoxemia, supplemental oxygen can be given. There are various types of oxygen delivery devices. Oxygen can be given through a breathing mask, a small tube placed in the nose (cannula). This can be given at home, in a small machine that you can take with you when you travel, or in the hospital.

How to manage symptoms?

If you suddenly feel confused, have difficulty breathing, have a fast heartbeat, or notice that your nails, lips, or skin are turning blue, you should seek medical attention immediately. If you have a pulse oximeter at home, you can also use it to check your oxygen levels. Hypoxemia must be treated quickly to prevent organ damage in severe cases.

People with certain conditions, such as COPD and Sleep Apnea, may experience hypoxemia on a regular or intermittent basis, but they may not experience any major symptoms. Therefore, talk to your doctor about how to manage your condition, reduce symptoms, and reduce the risk of low oxygen levels.

What complications can this cause?

When the oxygen level in the blood decreases, our organs and tissues do not receive the amount of oxygen they need to function. As we have already discussed, this is called `(Hypoxia).` If this condition continues, for example, due to `(Sleep Apnea)` and `(Nocturnal hypoxemia`), our heart and brain can be damaged. Sudden, severe hypoxemia can even be life-threatening.

How to reduce the risk?

The best way to reduce your risk of hypoxemia is to properly manage your underlying medical conditions. If you have lung or heart disease, talk to your doctor about specific ways to reduce your risk.

Even for people without heart or lung disease, the risk of hypoxemia can increase due to certain medications or when traveling to high altitudes. Therefore, ask your doctor about any medications you are taking and any special precautions you should take when traveling. When traveling to high altitudes, give your body enough time to acclimate.

What can you do to increase oxygen levels?

The best way to keep your blood oxygen levels safe and reduce the risk of hypoxemia is to properly manage your medical conditions.

• Don't forget about new symptoms. If you feel anything strange, pay attention to it. See a doctor or go to the emergency room.
• If your doctor has prescribed oxygen for you, use it properly.
• Take care of your lung health (`Pulmonary hygiene`). If you have ``COPD`` or asthma, know what triggers you have. Always keep your ``rescue inhaler`` with you. Use an ``incentive spirometer``, do breathing exercises, and follow other lung health tips your doctor gives you.
• If you smoke, stop. Quitting smoking improves lung function, allowing your lungs to take in more oxygen. It also prevents further damage to your lungs.
• Take the medicine exactly as prescribed by the doctor.
• Make a plan when traveling to high altitudes. Even for people without heart or lung conditions, it can be difficult to breathe at high altitudes. Think ahead about how it will affect you and how you will adjust to the change. Also plan ahead for what to do if you need emergency medical help. Take enough time to acclimatize if necessary, and bring any extra equipment or medications you may need.

When do you need to go to the hospital urgently?

Hypoxemia is a life-threatening condition. In such cases , you should immediately go to the Emergency Department (ETU) :

• If you have symptoms of hypoxemia, or if others notice a sudden change in your behavior or consciousness (restlessness, confusion, altered consciousness).
• If you have an ongoing medical condition, and your usual symptoms suddenly get worse, or if you develop new symptoms that you think may be due to hypoxemia.

What questions should you ask the doctor?

If your doctor tells you or a loved one that you have hypoxemia, you can ask them questions like these:

• Is this hypoxemia caused by another underlying medical condition?
• How should I manage my condition to reduce the risk of hypoxemia?
• Has this caused any organ damage or other complications?
• What lifestyle changes can reduce the risk of hypoxemia?
• Could changing my travel plans or changing my medications increase my risk of hypoxemia?

In summary (Take-Home Message)

So, in summary, hypoxemia is a condition where the oxygen level in the blood is low. This can sometimes be life-threatening. But it can be treated effectively if you seek medical attention quickly. Sometimes, for example, if you have ``Sleep Apnea'', you may have low oxygen levels at night without any major symptoms. If this continues, it can damage the heart.

Therefore, it is very important to be aware of your risk and what you can do to prevent it. If you have any doubts, don't be afraid to talk to a doctor. Stay healthy!

` Hypoxemia, lack of oxygen, difficulty breathing, lung disease, heart disease, oxygen level, cyanosis